fix blurblack theme suggestion font color not visible

Author: jjw24

Flow.Launcher/Themes/BlurBlack.xaml

@@ -1,4 +1,4 @@
-<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:system="clr-namespace:System;assembly=mscorlib">
     <ResourceDictionary.MergedDictionaries>
@@ -13,6 +13,7 @@
     </Style>
 
     <Style x:Key="QuerySuggestionBoxStyle" BasedOn="{StaticResource BaseQuerySuggestionBoxStyle}" TargetType="{x:Type TextBox}">
+        <Setter Property="Foreground" Value="LightGray" />
     </Style>
 
     <Style x:Key="WindowBorderStyle" BasedOn="{StaticResource BaseWindowBorderStyle}" TargetType="{x:Type Border}">